Water-conveyance apparatus



United States Patent Bonnie Vold Baker;

Robert M. L. Baker, lr., both of 4444 South Via Marina, Marina Del Rey, Calif. 90292 [2]] Appl. No. 760,532

[22] Filed Sept. 18, 1968 [45] Patented Oct. 6, 1970 [72] lnventors [54] WATER CONVEYANCE APPARATUS 25 Claims, 18 Drawing Figs.

Primury Examiner- Andrew H. Farrell AlmmeyFulwider, Patton, Rieber, Lee and Utecht ABSTRACT: Water-conveyance apparatus including a main frame supported from a plurality of vertically extending struts which are pivotally connected to the frame for pivoting about forwardly and rearwardly extending axes, some struts including transversely extending hydrofoils on their lower extremities. The struts can be pivoted in unison to adjust the angle of the hydrofoils relative to the horizontal to provide sufficient transverse hydrofoil force to balance oppositely directed transverse forces on the craft and thereby eliminate roll. Such pivoting of the struts and/or a shifting of a propulsion means carried on the frame transversely relative to the center of resistance to movement of the craft can also be employed to v steer such craft, it being understood that in a symmetrical craft, such center of resistance would be substantially along the longitudinal line of symmetry. The struts may also pivot about transverse axes'to selectively adjust the angle of attack of the hydrofoils and, when the craft is traveling at speeds below which the hydrofoils are efficient, the hydrofoils may be pivoted sufficiently forward to lower buoyant hulls, suspended from the frame, into the water to support the apparatus and enable the hydrofoils to be raised clear of the water to reduce drag. Also, the struts may be pivoted to an intermediate position such that two hydrofoils are submerged, but angled forwardly into the water in order to brake the craft and reduce or minimize its speed.

The water-conveyance apparatus may include a motor, generator, and electrical storage device The electric generator is engaged when the craft is under wind propulsion, the electrical energy is stored, and can be utilized at another time by the electric motor to provide for auxiliary propulsion.

The water-conveyance apparatus may also include an optimization system for processing data to establish optimum craft performance.

Patented Oct. 6, 1970 3,532,067

Sheet 1 of 5 INVENTORS. 05597 M4. BAKE JQ. Jaw/w: 1 040 .B/IKE'E ATTORNEYS Patented Oct. 6, 1970 FIG. l2

FIG.I5

'- TNVFNTORS. KOBE/Q7 ML. BAKER JR. BONN/' VOLD .Bfl/f' Arron NEYJ WATER CONVEYANCE APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a hydrofoil apparatus and more particularly to a hydrofoil apparatus including hydrofoils extending transversely of the direction of travel and which can be inclined to the right or left to provide trans verse hydrodynamic forces to balance oppositelydirected un stabilizing forces acting on the craft.

2. Description of Prior Art 'I-Iydrofoil, water-conveyance crafts have been proposed which include V-shaped hydrofoils to provide stabilizing forces acting inwardly from opposite sides toward the longitudinal, fore-toaft. line of symmetry ofthe craft. but hydrofoils of this type suffer the undesirable characteristic of creating opposed inwardly-directed horizontal forces acting inefficiently against one another. Other systems have been proposed which include vertical struts pivotable from transverse axes to adjust the angle of attack of hydrofoils mounted on their lower extremities, but there are no known crafts which include hydrofoil struts pivotable about longitudinal axes whereby such struts can be selectively inclined to the right or left to orient the hydrofoils and provide transverse hydrodynamic forces to balance opposed transverse forces on the craft thereby stabilizing it.

Water-conveyance crafts, especially submarine craft, have been propelled by electrical energy in the past, but the source of their electrical energy has been either chemical or nuclear in origin. For an aerodynamically propelled craft it is desirable to generate such energy while the craft is under wind propulsion and then to employ the stored electric energy to provide for auxiliary propulsion SUMMARY OF THE INVENTION The present invention is characterized by a main frame carried on vertical struts, connected to the frame on their upper extremities, and mounting hydrofoil slats on their lower extremitiesrMeans is provided for angling the hydrofoil slats longitudinally to provide transverse hydrodynamic forces to balance opposed transverse forces acting on the craft. The craft may be propelled by rigid air foils, or other propulsion means may be controlled by a self-adaptive guidance and control and design optimization device, and may include a generator, motor, and electrical energy storage device.

An object of the invention is to allow for an electrical-energy generation mode of operation while the craft is being aerodynamically propelled and an electric-motor propulsion system to provide auxiliary propulsion.

Another object of the invention is optimally to guide the craft and/or optimally utilize its energy resources by an automated sequential decision making process that involves the processing of data and data estimate variances on the crafts position and velocity, quantity of stored electric energy, and health and status of the craft as well as data and data-estimate variances on both the local and the remote environment of the craft.

Another object of the present invention is to utilize all forces on a hydrofoil craft to propel and stabilize the craft in an efficient fashion.

Another object of the present invention is to provide a hydrofoil craft which can be rapidly transferred from buoyant hulls to hydrofoils and vice versa at a selected craft speed.

Still another object of the present invention is to provide a hydrofoil craft having rigid airfoils which are maintained vertical even when exposed to athwartship winds.

Objects and features of the invention will become apparent from consideration of the following description taken in connection with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a water-conveyance apparatus embodying the present invention;

FIG. 2 is a partial broken perspective view ofa modification of the water-conveyance apparatus shown in FIG. 1;

FIG. 3 is a partial broken perspective view of a modification of a hull ofthe water-conveyance apparatus shown in FIG. I;

FIG. 4 is a perspective view similar to FIG. I, but showing the apparatus hydrofoil borne;

FIG. 5 is a diagrammatic view of the hydrofoil apparatus shown in FIG. 1;

FIG. 6 is a partial broken perspective view, in enlarged scale, of a modification of an airfoil of thewater-conveyance apparatus shown in FIG. 4;

FIG. 7 is a partial perspective view of a hydrofoilarrangement which may be utilized with the water-conveyance ap paratus shown in FIG. 1;

FIG. 8 is a horizontal sectional view, in enlarged scale, taken along the line 8-8 of FIG. 6;

FIG. 9 is a partial perspective view, in enlarged scale, of a modification of a hydrofoil strut of the water-conveyance apparatus shown in FIG. 1;

FIG. 10 is a vertical sectional view, in enlarged scale, taken along the lines 10-10 of FIG. 9;

FIG. 11 is a diagrammatic view of an electrical generating, storage, and propulsion system which may be utilized with the water-conveyance apparatus shown in FIG. 1;

FIG. 12 is an aft view of the water-conveyance apparatus shown in FIG. 1;

FIG. 13 is a horizontal sectional view of a modification of the water-conveyance apparatus shown in FIG. I and depicting a chain interconnecting the hulls for pivoting them in unison;

FIG. '14 is a broken vertical sectional view, in enlarged scale, taken along the lines 14-14 of FIG. 9;

FIG. 15 is a schematic diagram of forces which may act on the water-conveyance apparatus shown in FIG. 1;

FIG. 16 is a partial broken front view, in enlarged scale, the airfoils included in the water-conveyance apparatus shown in FIG. 1;

FIG. 17 is a side view of the airfoil shown in FIG. 16; and

FIG. 18 is a schematic of a data processing system which may be utilized with the water-conveyance apparatus shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT General Configuration Referring to FIGS. 1 and 4, the water-conveyance apparatus of the present invention includes a horizontal main frame M and a horizontal connector frame C disposed thereabove. A pair of struts S and S are disposed at the front-corners ofthe frames M and C and a third strut S" is disposed centrally at the back of the frames M and C, such struts mounting hydrofoil ladders F on their lower extremities. The struts S. S and S" are pivotally connected to the frames M and C whereby the connector frame C can be shifted sideways relative to the frame M to incline the struts S and correspondingly incline the hydrofoils F to angle the lifting force of such hydrofoils from the vertical and provide a transverse, or horizontal, force to balance opposed transverse forces, such as wind forces, acting on the craft to prevent roll. In the preferred embodiment-three vertical hulls H are supported from the connector frame C for buoyantly supporting the apparatus when the struts S are retracted as shown in FIG. 1. Three side-by-side rigid airfoils or sails A are mounted on the main frame M for providing propulsion to the apparatus. It should be understood that the size of such airfoils A may be varied depending upon the weight and desired speed of the water-conveyance apparatus.

Description of the Main and Connector Frames M and C, Struts S, and Hydrofoils F Referring to FIGS. 4 and 5, the main frame M includes a extends longitudinally of the frame end and is welded on its front end to the front member 31 and is welded on its rear end to the juncture of members 33 and 35. The connector frame C is of similar construction and includes a front member 41, a pair of side members 43 and 45 and rear members 47 and 49 which are joined together on their adjacent ends. A transverse brace 51 extends between the rear members 49 and 47 and a strut 53 is braced between the midpoint of the brace 51 and the juncture of members 47 and 49. A frame member 55 projects forwardly from the midportion of the front frame member 41 and is braced at its forward extremity by a pair of braces 57 and 59.

In order to enable the struts S, S and S" to pivot both transversely and forwardly they are connected to the frames M and C by pivot assemblies, generally designated 61 (FIG. 4) and such assemblies include hinge elements 65. Referring to FIG. 9, the hinge element 65 has one end journaled into a trans verse tube 67 carried on the respective strut and the element projects outwardly from such tube 67 and is bent to extend downwardly for a length 69, is then bent to extend inwardly for a length 71 and is finally bent rearwardly and journaled into a longitudinal tube 73 carried on the respective frame M or C.

The frames M and C are biased together by tension springs 74 (FIG. 9) to dampen relative movement therebetween.

For purposes which will be made apparent hereinafter, it is desirable to have capability of adjusting the vertical distances between the connector frame C and the main frame M. To this end, the upper extremities of the struts S, S and S" are formed by female housings 75, into the lower end of which is telescoped a plunger portion 76. Referring to FIG. 14, axial positioning of the plunger portion 76 within the housing 83 is controlled by a hydraulic cylinder 77 connected on its upper end to a transverse rod 78 mounted in the housing 75 and on its lower end to a cross rod 84 mounted in the plunger portion 76. The housings 83 may be capped by counterweights 79 which provide for relatively free rotation of the struts on their axes.

In order to utilize the lifting force of the hydrofoils F to adjust such hydrofoils to maintain craft stability in response to athwartship, or lateral, wind thrusts, the hydrofoils F on the front struts S and S' are spaced laterally outboard of the portion of the struts S and S' which connect them with the frames M and C. Referring to FIG. 9, the lower end of the plunger portion 76 receives a main strut section, generally designated 85, which includes an upper vertical portion 87 coupled with the plunger portion 76 by means of a thrust bearing (not shown), an angled portion 89, and a vertical lower portion 91 that receives a vertical member 93 of the hydrofoils F. In the embodiment shown a hand crank 95 is mounted from the plunger portion 76 and includes a worm screw which engages a worm gear 96 on the strut portion 87 to rotate the respective struts S or S to locate the axis 97 of the hydrofoils F at a selected lateral off-set distance from the axis 99 of the upper portion of the respective strut. This lateral off-set adjustment produces torques to balance or modify the strut inclination as will be more fully described hereinafter.

Referring to FIGS. 2, and 9, it will be clear that uniform adjustment of the forward and rearward inclination of the struts S, S and S", and the consequent angle of attack of the hydrofoils F can be accomplished by shifting the connector frame C forwardly or rearwardly relative to the main frame M. Under certain conditions it is desirable to adjust the angle of the hydrofoils F on a particular strut independent of the angle of attack of hydrofoils on other struts and such independent adjustment may be accomplished by hydraulic cylinders 105 (FIG. 9) mounted under the main frame M and including a forwardly projecting rod 107 which mounts a crossbar 109 on its forward extremity. Thus, the rod 107 can be extended to rotate the lower portion of the strut S forwardly to increase the angle attack of the respective hydrofoils F.

To cushion the effect of varying numbers of the hydrofoils F being submerged as such hydrofoils pass through crests and troughs of waves, shock absorption means may be provided as shown in FIG. 10. The shock absorption means includes a fitting 111 at the top of the central hydrofoil member 93 which telescopes into the lower end of the strut portion 91 and is formed with a downwardly facing shoulder 113 for abutting a similar shoulder 115 formed at the lower extremity of the strut portion 91. A plug 117 is secured within the member 91 and mounts a downwardly projecting central shaft 119 which projects into an open-ended bore 121 formed in the fitting 111. A compression spring 123 is interposed between the plug 117 and the fitting 111 to maintain the foils F biased downwardly and to absorb axial force variations. A pair of bleed holes 125 are included in the plug 117 to provide for restricted airflow from the chamber formed betweenthe plug 117 and-the fitting 111 to enhance shock absorption-A ball bearing assembly 127 is sandwiched between the lower end of the spring 123 and the fitting 111 to facilitate pivoting of the hydrofoil member 93 for purposes which will be made apparent below.

Referring to FIG. 12, the hydrofoils F include a plurality of transverse hydrofoil slats 131, 133, 135, 137, 139, and 141, the upper slats being somewhat longer and having a larger I angle of attack than the lower slats. Thus, as more hydrofoil lift is created by increases in speed of the hydrofoil apparatus the apparatus will be elevated further in the water and the upper slats will be raised out of the water. Precipitate nonnominal submersion of one or more of the sets of hydrofoil slats will result in an increase in vertical restoring force. This is due to the submersion of the larger area and the larger angle of attack upper slats. The hydrofoil slats 131, 133, 135, 137, 139 and 141, and/or control fin 327 preferably utilize metal cores and fiberglass surfaces to provide rigidity, ease of fabrication, and trouble-free service life. The hydrofoil mounting member 93 is rotatable in the strut portion 91 having its axis of rotation 97 disposed forward of the axis 142 of the vertical center of effort of the hydrofoil ladder F and is hydrodynamically shaped to water vane and cause the hydrofoil slats 131, 133, 135, 137, 139, and 141 to be oriented perpendicular to the direction of the craft independently of strut rotation or such an orientation can be maintained by a mechanical linkage (not shown) to and 96 or by other means.

Referring to FIG. 7, an additional means for varying the hydrofoil surface to provide optimum lift and reduce drag and cavitation at various speeds is an adjustable in length hydrofoil, generally designated 143, and including a pair of oppositely extending telescopical hydrofoils 144 and 145 projecting from the opposite ends of a hollow, main hydrofoil 141. Hydraulic pistons 147 and 149 are mounted within the main hydrofoil 141 for reciprocating the auxiliary hydrofoils 144 and 145 outwardly and inwardly to vary the hydrofoil surface. Hydraulic tubes 150 and 152 extend down the respective struts S, S and S" for supplying fluid to drive the pistons 147 and 149.

Description of Airfoils A and Hulls [-1 Referring to FIGS. 1 and 6, the airfoils A are carried on vertical masts 151 and preferably include main sections 153 and telescopic upper sections 155 whereby the airfoil surface can be adjusted. Telescoped into the upper end of the vertical mast 151 is an extendable post 159 which is reciprocated up and down by a hydraulic control piston 161 to shift the entire respective airfoils A up and down relative to their respective masts 151.

Carried on the upper end of the telescoping post 159 is a thrust bearing 165 having support rods 167 and 169 projecting from opposite sides thereof. A support plate 173 is suspended from the rods 167 and 169 by means of three slide pillow blocks 175, 177 and 179 and includes an elongated opening 180 for passage of the mast 151. A feed sprocket 181 is carried on the support rod 167 and controls positioning of the blocks and 177. An adjustment chain 183 projects around the sprocket 181 and extends centrally down the airfoil A to an area where personnel on the craft can have thereto.

Projecting from the top of the post 159 is a plunger rod 191 of a hydraulic cylinder (not shown) and the top end of such plunger rod is connected with the telescopical airfoil 155 by means of a coupling 193 whereby reciprocation r of the cylinder will raise and lower the airfoil 155.

Disposed along the rear edge ofthe airfoils A are symmetrically arranged split flaps 197 and 199 (FIG. 6) which are fixed at their forward edges to the airfoils by piano hinges 201 and are pivoted about such hinges by knee braces 203. The flaps 197 and 199 may, obviously, be positioned anywhere between a fully retracted position and a fully open position. Other liftenhancing devices include ailerons, leading and/or trailing edge flaps of the split, external airfoil, venetian-blind, slotted or double-slotted variety, or suction vevices (not shown).

Referring to FIGS. 2 and 6, the airfoils A are pivoted on the thrust bearings 165 by means of a rotatable collar 21] fitted over the lower portion of the central mast 151 and formed with a worm gear 215. A worm 217 is supported from the mast 151 by means of brackets 219 and is rotated by a hand crank 221. A lever arm 223 projects rearwardly from the collar 211 and is affixed on its rear end to A and carries a vertical rod 225 which has a horizontal ganging rod 227 affixed to its lower nects with the rear extremity of the other two airfoils A and adjustment of the collar 211 to move the rear extremity of the central airfoil A shown in FIG. 2 to adjust the airfoil angle of attack will, likewise, adjust the angle of attack of the other two airfoils.

Referring to FIGSv l6 and 17, a collar 231 is affixed to the upper extremity of the masts 251 and has a T-shaped bracket 233 projecting forwardly therefrom. Attached to opposite ends of the cross member of the bracket 233 are adjustment cables 235 and 237 which extend downwardly and rearwardly within the airfoil A and are connected to the rear extremity thereof at the lower end thereof. Turn buckles 239 and 241 are included in the cables 23S and 237 whereby such cables can be selectively tightened to warp such airfoils A throughout their length, as shown in FIG. 4, to provide a varied angle of attack throughout the length of the airfoil thereby accommodating the wind velocity profile throughout the vertical length'of such airfoil. Alternatively, the split flaps, ailerons, or other lift-enhancing devices may be sectioned vertically and independently adjusted in order effectively to modify the angle of attack throughout the airfoil's length as shown in FIG.

ready access Referring to FIGS. 1 and 2, the airfoils A are shown supported from a horizontal aerodynamic cabin, generally designated 251, and the mast 151 of the central airfoil projects downwardly through such cabin and includes a horizontal support rod 255 on its lower end, such rod resting on a slide 257 affixed to a beam 261, which is part of the main frame M. The cabin 251 and airfoils A may be shifted forwardly and rearwardly on the main frame M to selectively relocate the center of mass of the entire apparatus and such shifting. may be accomplished by a capstan 265 affixed to the mast 151 and having a chain 267 extending thereover. The opposite ends of the chain 267 are connected to the main frame by brackets 269 and 271, the chain 267 also extending over an idler 275 supported from the mast 151. Thus, rotation of the handle 279 of the capstan 265 will shift the airfoil A and cabin 251 forwardly and rearwardly on the main frame M. The cabin 251 and airfoils A could, likewise, be shiftable transversely to shift the center of mass to accommodate transverse forces.

Forwardly and rearwardly shifting of the interconnector frame C relative to the main frame M is accomplished by a capstan 285 supported from the central mast 151 and feeding a chain 287 thereover. The front end of the cabin 287 is affixed to the cross member 41 by means of an athwartship slide 291 and the rear extremity of such chain is affixed to the rear extremity of such chain is affixed to the rear cross member 51 by an athwartship slide 293 whereby the ends of the chain 287 end. The gauging rod 227.com

ment ofsuch chain is accomplished by the rear extremity of the airfoil are free to move sideways to enable the interconnector frame C to move transversely relative to the main frame M. The adjustment chain 287 feeds under an idler pinion 289 and adjustgrasping and rotating a hand crank 297 secured to the capstan 285. The crank 297 may be rotated slightly to alter the angle of attack of the submerged hydrofoils F or the hydrofoils F may be rotated to their extreme forward position shown in FIG. 1 anda pelican hook 301 may be secured around the members 35 and 45 of the main frame M and the interconnector frame C to maintain such hydrofoils retracted.

Referring to FIGS. 1 and 3, the bulls H are aerodynamically shaped and are supported from the connector frame C by vertical axles 311 (FIG. 3) which are carried in bearings included in the frame and mountsprockets 313. The sprockets 313 are rigidly affixed to the upper ends of the hulls H and all sprockets,313 are coupled together by an endless connecting chain 319*(FIG. 13). A drive sprocket 321 engages the chain 319. intermediate the forward hulls whereby such hulls can be pivoted on their respective axes in concert. It will be clear that the bulls H may be shiftable relative to the axles 311 to establish the aerodynamic force through the vertical axis including such axles similar to the above-described shifting of the airfoils A.

Referring to FIG. 3, the lower portions of the hulls H are formed with downwardly-opening chambers 325. which receive telescopical vertical control fins 327 carried on the plunger rod 329 ofa hydraulic cylinder 33 1.

Referring to FIG. 11, an electric generator 341 is mounted on a platform 342 carried in the cabin 321 or in the, airfoils 197 and includes a drive shaft 343 projecting from both ends and coupled on one end with a variable-pitch propeller 345 by means of a universal joint 347. An electric motor 351 is supported on the plate 342 and the generator driveshaft 343 extends therethrough, a hollow drive shaft 353 projecting from the motor and arranged co-axially with the drive shaft 343 and mounting a clutch 355 on its projecting end. A hollow shaft 357 projects rearwardly from the generator 341, receives the shaft 343, and mounts a clutch 359. and. the motor shaft 353 can be selectively engaged with the propeller shaft 343 by means of the clutches 355 and 359. The Y selectively be connected of a double throw switch generator 341 and motor 351 can with a storage battery 361 by means 363 whereby the generator 341 may be driven at-certain periods of time to store electrical energy and subsequently I therefromby the motor 351 electrical energy may be removed to drive the propeller 345 whereby such propeller may,.alternatively, act as a water screw. The universal joint. 347 enables the propeller 345 to be directed into theapparent wind as represented by directional arrows 364. Rather thanv have the propeller 345 also act as a water screw, propellers 365 (FIG.

1) may be mounted on the cabin 351 or airfoils. and a hollow drive shaft (not shown) may be coupled with the rotary shaft 366 projecting from the right hand end of the motor 351 for driving a conventional water screw (not shown) mounted from the apparatus.

OPERATION When the water-conveyance apparatus is at rest or operatingat low speeds the hydrofoil adjustment crank 297 (F IG. 2)

is adjusted to move the connector frame C rearwardly with respect to the main frame M in the position shown in broken lines in FIG. 9 thereby raising the hydrofoils F out of the water as shown in FIG. the main frame M l. The pelican hooks 301 are hooked over to accommodate the vertical profile of the wind velocity. The 1 individual airfoils A are shifted forwardly or rearwardly on their respective masts 151 by pulling on the adjustment chains 3 The generator shaft 357 to maintain the hydrofoils in their retracted positions. When the craft is under way the turn buckles.239

183 to thereby direct the resultant force on each through the respective supporting masts 151 thereby eliminating any torque between such airfoils and masts. Such shifting may also be utilized to create a torque on the airfoils A to cause them to pivot on their masts 151 to adjust the angle of attack. The extendable airfoils 155 may also be extended to provide greater airfoil area or, in the case of high winds, such airfoils 155 may be retracted. Each airfoil A is also adjusted vertically on the mast 151 by the elevating cylinders I61 thereby shifting the resultant force vertically to provide optimum dispositon thereof for craft stability.

When the craft reaches the optimum lift-off speed, the pelican hooks 301 are unlatched and the capstan 285 permitted to rotate freely to enable the hydrofoils F to drop downwardly and submerge in the water. Referring to FIGS. 1 and 12, it will be clear that submergence and elevation of the hulls H will be rapid because the entire apparatus moves upwardly and forwardly on the struts much as a pole vaulter when he is vaulting. This overcomes the inefficiency of slow submergence of the hydrofoils and continued drag of the hulls H after the optimum lift-offspeed has been reached.

The optimum lift-off speed is the speed above which hydrofoils are more efficient than hulls and is given approxi mately by the equation:

g is the acceleration of gravity.

M is mass of the craft.

p is the density of the water.

is is the proportionality constant of effective hull drag area and is equal A/A where A is the submerged cross sectional area of the hulls and A is the displacement of the hulls.

(L/D) is the lift-to-drag ratio of the entire submerged system.

Since C (L/D) is a function of craft speed, the solution for V, the optimum lift-off speed, is an iterative one.

Over-rotation of the struts S, S and S" rearwardly is prevented by the transverse stops 109 (FIG. 9) on the main frame M and adjustment in concert of the angle of attack of the hydrofoils F may be accomplished by actuating the adjustment capstan 285 to shift the connector frame C forwardly or rearwardly with respect to the main frame M to thereby establish selected angles of forward inclination of the struts S, S or S Individual ones of the struts S, S or S" may be adjusted to compensate for paticular wind thrusts and effect turning of the craft by actuating the control pistons 105 mounted to the frame M to move the stops 109 forwardly or rearwardly.

An inclination can thereby also be maintained such that the hydrofoils are submerged, but angled forwardly into the water in order to brake the craft and reduce or minimize the craft's speed.

Referring to FIG. 12, it will be clear that at speeds only slightly greater than the optimum lift-off speed the entire hydrofoil ladders F will be submerged thereby submerging all the hydrofoil slats 131, 133, 135, 137, 139, and 141 and providing maximum hydrofoil lift. The maximum total hydrofoil area A is related to the optimum lift off speed by the equation A is the maximum total hydrofoil area.

My is the weight of the eraft.

L is the aerodynamic lift of cabin, structural members, and vertical component of the aerodynamic lift of the hydrofoil slats raised out of the water when the struts are down.-

p is the density of the water;

C is the overall lift coellieient of the hydrofoils; and

V is the optimum lift elf speed as determined supra.

Thus, the overall hydrofoil area will be determined by the above equation and the number and length of hydrofoil slats 131, 133, 135, 137, 139, and 141 will be determined by the weight of craft and expected speeds for the particular propulsion system utilized. It will be clear that as the craft speed increases beyond optimum lift-off speed V the hydrofoil lifting forces will become greater thereby raising the craft further in the water and raising the upper hydrofoil slats in the ladders out of the water and reducing the overall hydrofoil area. Such a feature is of particular importance to avoid cavitation and undue drag on the hydrofoils. For the hydrofoils shown in FIGS. 7 and 9, the telescopical hydrofoils 143 and 145 may be extended and retracted in accordance with the velocity of the craft.

Of particular importance is the fact that automatic adjustment of the lateral angle of the hydrofoils F is provided to compensate for side thrusts. When there is no sideways thrust on the airfoils A the hydrofoils F and control fins 327 are in equilibrium thereby causing the craft to move directly forward balanced on the respective hydrofoils F as shown in FIG. 12. Referring to FIG. 4, as the wind velocity 331 increases the lateral force on the airfoils A will also increase thereby exerting a lateral force on the main frame M urging it sideways with respect to the connector frame C. The hulls H suspended from the connector frame C resist sideways shifting because of the vertical control fins 327 which offer more resistance to lateral movement than the hydrofoils F thereby causing the struts S, S and S" to pivot about their longitudinal axes to move the respective hydrofoils to an orientation having an increased slope along their respective lengths in accordance with the velocity 331 of the wind. The stability of the craft can also be maintained by controlling the inclination of the struts S, S and S" and when the craft is so operating the control fins 327 can be fully retracted by the cylinders 331 to reduce drag.

Consideration of the forces acting on the craft and how the various craft components are manipulated to maintain craft stability can best be understood by considering only one strut. Referring to FIG. 15, it will be assumed that the craft is to be moved along the extended axis of symmetry 375 of the main frame M in the direction indicated by directional arrow 377. For purposes of explanation, the main frame M is considered as being in a horizontal plane 378 and the strut S is in a vertical plane 379. The wind 380 blowing across the airfoils A creates a thrust 381 which can be broken into a transverse horizontal component 383 and a longitudinal horizontal component 385. The airfoils A may be shifted to have the center of effort thereof act at the point CE and the strut S may be angled to have its lifting force 387 of the hydrofoil F can be broken into a vertical component 393 which is equal to the weight M,, of the craft and a horizontal component 395. which is equal and opposite to the horizontal component 383 of the thrust vector 381. It will be recalled that the hydrofoil F may be moved laterally by rotating the struts S. S and S" by hand crank and the equilibrium balance between the hydrofoils and control fins also may be changed by extending or retracting the pistons 77 to alter the distance between the frames M and C. It is of particular importance to note that by eliminating roll of the craft the airfoils A are maintained vertical to prevent the lost efficiency which would result from an inclined airfoil A.

The drag 399 of the hydrofoil F will create a torque in the vertical plane which may be countered by moving the center of mass CM forwardly or rearwardly along the line of symmetry 375 to create a countercouple due to the propulsive thrust vector being offset from the CM. A counterweight 376,

which may be the airfoils A and the cabin 251, is moved forwardly or rearwardly by the capstan 265 (FIG. 2) to position the center of mass CM so as to null out pitch of the craft.

When the craft is headed close to the apparent wind it is desirable that the airfoils have a large effective aspect ratio to reduce induced drag and increase the lift-to-drag ratio. On the other hand. when the wind is from the port or starboard, a large coefficient of lift is desirable and to this end the aforementioned flaps 197 may be extended to increase the lift coefficient.

Guidance System Operation It will be clear that rather than relying on manual adjustments of the foregoing components some, or all, of the adjustments could be automated. A self-adaptive, optimal, guidance and control system which may be utilized to continuously monitor and control the craft by means of a craft simulation and a sequential processing of observational data is shown diagrammatically in'FlG. 18. Such a system can also be employed and specify optimum design improvements by sequentially processing data. The control system moves the apparatus of the water-conveyance automatically in response to the sensed motion of the conveyance, data collected on the local and remote environment, and in response to human commands. The extent of apparatus'motion resulting from control-system commands can be varied asa function of the sensed motion of the conveyance and/or manual adjustments of electronic ele,

ments. The control-system causes moments and forces to be applied to the water-conveyance apparatus, thus modifying the motion of the water-conveyance apparatus.

Electrical System Operation absence of wind, independently drive such craft through the water.

When the generator 341 is being driven by a wind propeller 345 and the apparent winddirection does not coincide with the line of symmetry of the water-conveyance apparatus it is valuable to include a coupling 347 ora flexible shaft (not shown) between the propeller 345 and the generator 341m order to orient the propeller 345 so as to achieve a propeller alignment withthe apparent wind. When the electric motor 351 is driving a wind propeller 345 the foregoinglogicalso recommends the use of the coupling 347 or a flexible shaft (notshown).

From the foregoing it will be apparent that the water-conveyance apparatus of the present invention provides means whereby a hydrofoil system can be manipulated and maneuvered without the normal inefficiencies induced by keels, rudders and V-shaped hydrofoils. The entire forces acting on the craft are utilized for propulsion, lift, and to induce stability thereby making the most efficient use of the available wind and propellingthe craft at the maximum speed.

Various modifications and changes may be made with regard to the foregoing detailed description without departing from the spirit of the invention or the scope of the following claims.

We claim:

1. Water-conveyance apparatus comprising:

a main frame;

a plurality of downwardly extending struts mounted on said frame;

transverse hydrofoil means mounted on the lower extremities of the respective struts; and

control means for tilting said hydrofoil means in the same transverse direction whereby when an unstabilizing force acts on said apparatus said hydrofoil means may all be tilted in the same direction to cause the hydrodynamic force on each said hydrofoil means to create a corrective transverse force acting opposite said upsetting force to thereby tend to stabilize said apparatus.

2. Water-conveyance apparatus as set forth in claim 1 wherein said hydrofoil means includes a plurality of vertically spaced hydrofoil slats on the lower extremities of said respective struts, the upper hydrofoil slats being longer than the lower hydrofoil slats.

3. Water-conveyance apparatus as set forth in claim 2 wherein the angle of attack of the upper slats is greater than the angle of attack for the lower slats.

4. Water-conveyance apparatus as set forthin claim I that includes a buoyant hull supported from said main frame whereby said apparatus can selectively be supported by hydrofoils and said hull.

5. Water-conveyance apparatus as set forth in claim 4 wherein:

said struts are pivotal about transverse axes whereby said hydrofoils may be supported in an elevated position forward of the respective strut pivot axes while said apparatus is supported on said hull and may be lowered at a predetermined speed to raise said apparatus on said hydrofoil; and

wherein said apparatus includes means for supporting said struts in position with said hydrofoils elevated.

6. Water-conveyance apparatus as set forth in claim 1 wherein:

said struts are pivotally attached to said main frame for rotation about forwardly and rearwardly extending axes; and said control means includes a connector frame pivotally connected to said struts to move said struts in unison to vary the angle of said hydrofoil means to provide said transverse forces.

7.. Water-conveyance apparatus as set forth in claim 6 wherein said connector frame is disposed above said main frame;

said propulsion means includes an airfoil mounted on said main frame; and

wherein said apparatus includes:

a longitudinal control fin mounted from said connector frame for submersion in the water. as said craft travels therethrough to provide greater resistance to transverse movement of said connector frame than said hydrofoil means provides for said main frame whereby when wind imparts a transverse thrust to said airfoil said main frame will 7 be shifted in the transverse, direction of said wind a greater distance than said connector frame thereby causing the lower extremities of' said struts to be angled in the direction of said wind to orient said hydrofoil means to provide a lifting force having a transverse component substantially equal and opposite to the transverse force of said wind thrust whereby said hydrofoil means will resist further trans verse movement of said apparatus in the direction of said wind.

8. Water-conveyance apparatus as set forth in claim 6 that includes biasing means connected between said main frame and said connector frame to dampen relative movement therebetween.

9. Water-conveyance apparatus as set forth in claim 8 wherein said struts include adjustment means interposed between said main and connector frames for independently adjusting the distance, along the respective struts, between the main and connector frame to adjust the torqueon said respec tive strutsaffectedby said transverse thrust and modify the amount of submergence of said control fin.

l0. Water-conveyance apparatus as set forth in claim 1 wherein said hydrofoil means includes means for varying the hydrofoil area to improve hydrofoil efficiency.

11. Water-conveyance apparatus as set forth in claim 1 wherein said struts include shock absorbing means for absorbing erratic lifting forces on said hydrofoil means.

12. Water-conveyance apparatus as set forth in claim 11 wherein:

said rigid airfoil is flexible; and

said apparatus includes torque means connected. between the upper and lower portions of said airfoil for selectively warping said airfoil to provide a progressively varying angle of attack along the vertical span of said airfoil.

l3. Water-conveyance apparatus as set forth in claim I wherein said propulsion means includes a substantially rigid airfoil supported from said main frame.

14. Water-conveyance apparatus as set forth in claim 13 that includes means for pivoting said airfoil to vary the angle of attack.

15. Water-conveyance apparatus as set forth in claim 13 wherein said airfoil includes means extending along and connected to the edges of said airfoil for selectively altering the lift of said airfoil.

l6. Water-conveyance apparatus as set forth in claim 13 wherein said airfoil includes:

a main airfoil formed with an open ended vertical passage;

an extendable airfoil telescoped into said passage; and

means for extending said extendable airfoil to adjust the airfoil surface.

17. Water-conveyance apparatus as set forth in claim 1 wherein:

said struts are pivotable about a transverse axis; and

that includes means for adjusting the angle of said struts to adjust the angle of attack of said hydrofoils.

l8. Water-conveyance apparatus as set forth in claim 1 that includes a horizontally extending structure having an airfoil cross section whereby wind passing over said structure will effect a lifting force thereon.

l9. Water-conveyance apparatus as set forth in claim 1 that includes:

a mast supported by said main frame;

an airfoil supported on said mast; and

means for shifting said airfoil vertically on said mast to adjust the center of effort to stabilize said apparatus. I

20. Water-conveyance apparatus as set forth in claim 1 that includes:

a vertical mast supported on said main frame;

a rigid airfoil supported by said mast; and

means for shifting said airfoil horizontally on said mast to selectively shift the center of effort of said airfoil relative to said mast.

2]. Water-conveyance apparatus as set forth in claim 1 that includes:

a balancing weight; and

means for shifting said weight on said main frame to stabilize said apparatus.

22. Water-conveyance apparatus as set forth in claim 1 wherein said hydrofoil means includes:

main hydrofoils mounted on the respective struts and formed with longitudinal open ended passages; telescopical hydrofoils disposed in said respective passages;

and

means for extending said telescopical hydrofoils from said passages to selectively increase the respective hydrofoil areas.

23. Water-conveyance apparatus as set forth in claim 1 wherein:

said struts are pivotally attached to said frame for rotation about forwardly and rearwardly extending axes; and

said control means rotates said struts to vary the angle of said hydrofoil means to provide said corrective transverse forces.

24. Water-conveyance apparatus as set forth in claim 1 that includes a means for adjusting or maintaining the lateral balance of the said struts by off-setting said struts in an athwartship direction relative to their axes to swing said struts out to the side of the water-conveyance apparatus that allows the said hydrofoil force to counteract any said transverse force acting on the water-conveyance ap aratus and thereby eliminate roll, yaw, and si e-slip an for producing yaw torques for steering.

25. Water-conveyance apparatus as set forth in claim 1 wherein said propulsion means includes a plurality of airfoils mounted on said main frame and arranged in side-by-side relationship along an athwartship axis to provide a relatively low center of effort. 

